The invention relates to a magnetic head for recording and/or reproducing magnetic information in a track of a magnetic information carrier, comprising a magnetic core having two core limbs formed from a ferrite. The core limbs constitute two core faces located opposite each other, at least one of said core faces having a cladding of a soft-magnetic material having a higher saturation magnetization than the ferrite. The magnetic head also comprises a tape contact face along which the information carrier is movable, a non-magnetic transducing gap present between the core faces and terminating in the tape contact face, which gap has at least one layer of a first metallic material and bonded layers of a second metallic material, the first metallic material being chosen from the group of Mo, Ti, Cr and NiCr, and an electric coil passing through a winding aperture and surrounding a part of the magnetic core.
Such a magnetic head is known from European Patent Application EP 0,273,496 (PHN 11.962; herein incorporated by reference).
It is generally known to use ferrites such as monocrystalline Mn-Zn ferrite as a magnetic core material for magnetic heads. Among the advantages of such ferrites are a high resistance to wear, a relatively high specific resistance and satisfactory magnetic properties as regards coercive force and permeability.
Magnetic fields which are generated by a magnetic head at the area of the transducing gap for writing information on a magnetic medium are directly dependent on the saturation magnetization of the material of the magnetic head core. The above-mentioned ferrites generally have a saturation magnetization which is sufficiently high to write information on conventional tapes such as CrO.sub.2 tapes having a coercive force H.sub.c of approximately 700 Oersted. For recording information on magnetic tapes having a higher coercive force, such as ME magnetic tapes based on Co-Ni, conventional magnetic heads which exclusively have a ferrite at both sides of the transducing gap are less suitable. The magnetic fields which are generated by such magnetic heads to write information on a magnetic medium are in fact limited by the relatively low saturation magnetisation of the ferrite. The strength of the writing field is therefore insufficiently high to ensure optimum writing of magnetic tapes having a high coercive force.
A stronger writing field is achieved with the magnetic head disclosed in said EP 0,273,496. This known magnetic head has a transducing gap extending between two core limbs, which gap is composed of a plurality of layers of non-magnetic material. Each core limb has a core face opposite the gap, which face is provided with a cladding of Ni.sub.80 Fe.sub.20 by means of sputtering. An insulation layer at SiO.sub.2 of the transducing gap is provided on each Ni.sub.80 Fe.sub.20 cladding. A layer of Mo is provided on each insulation layer and a layer of Au is provided on each Mo layer, the Au layers being bonded to each other by means of thermocompression.
It is noted in EP 0,273,496 that the SiO.sub.2 insulation layer in the transducing gap functions as a barrier between the soft-magnetic material of the cladding which is formed, for example, from an alloy based on Ni-Fe or Fe-Al-Si, and the metallic materials of the transducing gap, thus preventing an electrochemical interaction between cladding and transducing gap. A drawback of the SiO.sub.2 insulation layer which is present is its relatively poor adhesion to the cladding layer.